@article{oai:niigata-u.repo.nii.ac.jp:00002226,
 author = {Akiyama, Hisashi and Sasaki, Osami and Suzuki, Takamasa},
 issue = {25},
 journal = {Optics Express, Optics Express},
 month = {Dec},
 note = {A sinusoidal wavelength-scanning interferometer for measuring thickness and surfaces profiles of a thin film has been proposed in which a superluminescent laser diode and an acousto-optic tunable filter are used. The interference signal contains an amplitude Zb of a time-varying phase and a constant phase α. Two values of an optical path difference (OPD) obtained from Zb and α, respectively, are combined to measure an OPD longer than a wavelength. The values of Zb and α are estimated by minimizing the difference between the detected signals and theoretical ones. From the estimated values, thickness and surface of a silicon dioxide film coated on an IC wafer with different thicknesses of 1 μm and 4 μm are measured with an error less than 5 nm.},
 pages = {10066--10074},
 title = {Sinusoidal wavelength-scanning interferometer using an acousto-optic tunable filter for measurement of thickness and surface profile of a thin film},
 volume = {13},
 year = {2005}
}